On the brink of a midlife crisis, 30-something Mike O'Donnell (Matthew Perry) wishes he could have a "do-over." And that's exactly what he gets when he wakes up one morning to find he's 17 years old again. With his adult mind stuck inside the body of a teenager (Zac Efron), Mike actually has the chance to reverse some decisions he wishes he'd never made. But maybe they weren't so bad after all. Leslie Mann and Michelle Trachtenberg co-star.